Author: Juan Roy Couto

Juan is a certified MongoDB Subject Matter Expert, helping DBAs and developers with certification exams. Currently, he works as a Senior MongoDB DBA. Before that, he worked for 20 years as a developer for various financial companies. You can read him at twitter.com/juanroycouto.

The Beginner’s Guide to MongoDB Aggregation (With Exercise)

Get an understanding of the MongoDB Aggregation Framework and how to take advantage of indexes to speed up queries.

Posted on: 03/07/2024 (last updated: 09/10/2024) • Juan Roy Couto • 14 minutes

How to Find & Filter MongoDB Array Elements Using $elemMatch

Learn how to filter elements from arrays in MongoDB by using the $elemMatch operator alongside find(), $match, and the $project and $filter functions.

Posted on: 16/10/2020 (last updated: 13/03/2024) • Juan Roy Couto • 8 minutes

MongoDB Users and Roles Explained – Part 2

Part 2 of our MongoDB Users & Roles Explained series walks you through how to enable access control on a three data-bearing node replica set, create the first user making use of the localhost exception, and grant the needed MongoDB roles.

Posted on: 18/09/2018 (last updated: 28/04/2025) • Juan Roy Couto • 5 minutes

MongoDB Users and Roles Explained – Part 1

Read Part 1 of our MongoDB Users and Roles Explained series to learn about the basics of MongoDB authentication, authorization, and user and role management.

Posted on: 18/09/2018 (last updated: 06/11/2023) • Juan Roy Couto • 9 minutes